ISOLDE Powering and ELENA

1. ISOLDE Powering and ELENA David Nisbet ELENA Powering 24/1/2012

2. Intro • Introduction - powering the ISOLDE complex • DC Systems v pulsed systems • Powering Bends, Quads and Steerers • Controls and diagnostics • Estimate of ELENA requirements • Conclusions ELENA Powering 24/1/2012

3. Introduction - powering the ISOLDE complex • Machine layout ELENA Powering 24/1/2012

4. Introduction - powering the ISOLDE complex • The ISOLDE complex, with many beam lines, is a diverse user of beams, beam treatment and experiments • Currently the entire complex uses >500 systems under the management of TE-EPC • Grouped into >50 different types • Range from [10V to 60kV] and [500uA to 1kA] • The many beam treatments in the complex leads to a large diversity of equipment (see Fredrik Wenander presentation) • Also due to the historical ‘growth’ of the complex through CERN and non-CERN developments ELENA Powering 24/1/2012

5. Introduction - powering the ISOLDE complex • The power converter types at ISOLDE ELENA Powering 24/1/2012

6. DC electrostatic powering • Recommendation • Minimise the flavours found in the accelerator • Cheaper; easier to operate and maintain; • As the systems are DC • Very low power is required • Systems are physically small -> up to 30 per rack ELENA Powering 24/1/2012

7. DC electrostatic powering • The power converter types used for ISOLDE transfer lines and recommended for use on future projects • If the proposals don’t fit with the accelerator needs • Straight forward to extend up to 35kV and 35W • Try to standardise! http://www.fug-elektronik.de/webdir/PDF/e/e_datasheet_HCE.pdf ELENA Powering 24/1/2012

8. Pulsed electrostatic powering • Additional constraints on the choice of power converter • Power source needs to sink and source current quickly • Peak current and power is much higher • The voltage rise and fall time is a critical parameter • Not available ‘off the shelf’ from commercial suppliers • EPC currently have very few pulsed systems in the ISOLDE complex • Kickers are required for ejection from ring and into experimental areas • These are generally the responsibility of the TE-ABT group • Check if the ABT group already have appropriate technology • ELENA will probably need pulsed quads to compensate dipole effects • Typical solution would switch rapidly between 2 DC sources using semiconductor switches; other solutions can be envisaged. • Synergy with kicker technology? Otherwise some development required. ELENA Powering 24/1/2012

9. Powering bends, quads and steerers • Preferred configurations if permitted by optics: 1x unipolar 1x unipolar 4x unipolar Bending configuration 1x negative 1x positive Quad configurations Steerer configuration ELENA Powering 24/1/2012

10. Controls and diagnostics • For DC systems, we currently use PLCs in the ISOLDE complex • Provides a slow control and acquisition solution for general monitoring • Acquisition of output voltage and power system state is generally sufficient • Specification of setpoint and measurement performance? 10-4resolution and 10-4 absolute ? • Acquisition of Pulsed Systems • In addition to the slow (PLC) control, triggers and fast acquisition are required • Standard solutions available from the CO group would typically be used • Check also synergies with the TE-ABT group ELENA Powering 24/1/2012

11. An ELENA TL shopping list for power Approx budget: 500 kCHF ELENA Powering 24/1/2012

12. Conclusions • Simple approach is best for the many small DC power sources required • Only a few types need to be considered compared to ISOLDE complex • Straightforward to extend to 35kV for modest cost • Pulsed approach needs much more care • Load capacitance, switching times, diagnostics • Possibly the TE-ABT group have a solution ready to go? • Consideration should be given to diagnostics requirements • Acquisition rateand acquisition performance (eg 10-4 absolute measurement performance required?) ELENA Powering 24/1/2012